I don't ever adjust to a table. The table has to adjust to me.
What I mean by that is I have to make changes to the table and chair so that I am seated the most comfortably. Because I'm really short, I always have a footrest, my back has to be fully supported either by a good chair or a backrest, and my chair always has to be adjusted to the right height.
Table ergonomics are very important and shouldn't be overlooked, so I never start drawing until I have all that in place. Apart from being able to draw better...severe back pain with pain shooting down your legs is not funny, and guaranteed to happen eventually if bad sitting posture continues.